Battery cost are still falling 10-15% a year. $100 kWh batteries are here already. ie Tesla battery costs per car ie 50kwh are $5500-6000 Musk is selling $35k+ not because he can't make cheaper cars but because he can make higher margins on expensive cars with battery production capacity he has. We will get high quality cheap electric cars once the battery production capacity is higher than the demand for expensive cars. Which will be here a lot faster than people are thinking.